Active control type fully-immersed liquid-cooled power battery thermal management system

Abstract

The invention aims to provide an active control type fully-immersed liquid-cooled power battery thermal management system. A compressor, a condenser, a refrigeration electromagnetic valve, an expansion valve and an evaporator are connected in series to form a compressor unit main refrigeration unit; a manual valve and a liquid spraying electromagnetic valve are led out from a pipeline in front of the refrigeration electromagnetic valve to form a spraying branch; a thermal manual valve and a thermal electromagnetic valve are led out from a pipeline between the compressor and the condenser to the evaporator to form a thermal bypass branch; and a first three-way reversing valve and a second three-way reversing valve are connected with a plate heat exchanger and the evaporator and are connected in parallel to form a plate heat exchanger auxiliary cooling unit, the first three-way reversing valve is connected with a drying filter and the manual valve to a cooling liquid tank, and the second three-way reversing valve is connected with an electronic circulating pump, a temperature sensor and a flow sensor to the cooling liquid tank. The direct contact type fully-immersed liquid-cooled mode is adopted, the heat loss in the heat exchange process of the whole heat management system can be greatly reduced and improved, the heat exchange resistance of the system is reduced, and the heat exchange efficiency is improved.

Description

technical field [0001] The invention relates to a power battery management system. Background technique [0002] Power battery, motor and electronic control technology are the core "three electric" components of new energy vehicles, and their performance has an important influence on the whole vehicle. Especially the current power battery is developing in the direction of high energy density and short charging time. The high heat output of power battery requires a thermal management system to dissipate heat quickly to ensure that the entire battery module or battery pack is in a suitable operating temperature range and different systems. Location cell temperature uniformity. [0003] At present, the existing power battery thermal management methods mainly include: air cooling, liquid cooling, phase change material cooling and heat pipe cooling. The heat management method of air-cooled power batteries is due to the small specific heat capacity of air, low thermal conductivi...

AI Technical Summary

Problems solved by technology

The heat management method of air-cooled power batteries is due to the small specific heat capacity of air, low thermal conductivity, small convective heat transfer coefficient, long time required for heat dissipation, poor cooling effect at high charge and discharge rates, and large inlet and outlet pressure differences of the entire system. Uneven, the difference in cooling conditions between the cells in the battery pack will lead to a large temperature difference in the battery pack, which has been gradually eliminated by the main engine factory

The thermal conductivity of phase change materials is low, the latent heat of phase change is small, and the amount of heat transfer is limited. It requires additional system volume and heavy weight, which greatly reduces the mass energy density and volume energy density of the entire thermal management system, and cannot dissipate heat in time. The problem of difficult preheating in thermal management of phase change materials is even more difficult to solve

Heat pipes and batteries have high requirements for shape adaptability, complex structures, poor heat transfer performance, high insulation requirements, high processing technology requirements and high costs

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